Polymers, underlayer coating compositions comprising the same, and patterning methods

ABSTRACT

A polymer comprising a first repeating unit including an amino group protected by an alkoxycarbonyl group; a second repeating unit including a nucleophilic group; and a third repeating unit including a crosslinkable group, wherein the first repeating unit, the second repeating unit, and the third repeating unit are different from each other.

FIELD OF THE INVENTION

This invention relates to polymers, their use in underlayer coatingcompositions and to patterning methods using such underlayer coatingcompositions. The polymers, compositions and methods of the inventionfind particular applicability to the semiconductor manufacturingindustry in the formation of semiconductor devices.

BACKGROUND

Photoresists are photosensitive films for transfer of images to asubstrate. After coating a photoresist on a substrate, the coating isexposed through a patterned photomask to a source of activating energysuch as ultraviolet light to form a latent image in the photoresistcoating. The photomask has areas opaque and transparent to activatingradiation that define an image desired to be transferred to theunderlying substrate. A relief image is provided by development of thelatent image pattern in the resist coating. The images formed can be ofpositive- or negative-type depending on the photoresist and developerchemistries.

Known photoresists can provide features having resolution and dimensionssufficient for many existing commercial applications. However, for manyother applications, the need exists for new materials and processes thatcan provide highly resolved images of submicron dimension.

Reflection of activating radiation used to expose a photoresist oftenposes limits on resolution of the image patterned in the photoresistlayer. The amount of scattering and reflection of imaging radiation willtypically vary from region to region, resulting in further linewidthnon-uniformity. Variations in substrate topography also can give rise toresolution-limiting problems.

One approach used to reduce the problem of reflected radiation has beenthe use of a radiation absorbing layer interposed between the substratesurface and the photoresist coating layer. Such layers have also beenreferred to as antireflective layers, BARCs, or underlayers. See U.S.Pat. No. 9,541,834; US20150212414; U.S. Pat. No. 6,767,689B2; U.S. Pat.No. 6,887,648B2; and U.S. Pat. No. 8,623,589.

With continuing reductions in feature sizes of semiconductor devices,photoresist patterning defects in the form of pattern collapse duringphotoresist development have become more pervasive. This is particularlyproblematic for pillar and line/space patterns formed in ArF and EUVlithography. A large pattern collapse margin would be desired to allowfor an improvement in lithography process window.

Pattern collapse margin is largely dependent on film properties of thelayer below and in contact with the photoresist layer, for example, aBARC or EUV photoresist underlayer. Control of basicity of theunderlayer at the interface with the photoresist layer can positivelyimpact pattern collapse margin. To control basicity of the underlayer,the use of photobase generator additives or photo-decomposable quencher(PDQs) additives are known. The concentration of such additives in thesurface region of the underlayer can, however, become reduced duringphotoresist spin-coating due to dissolution in the photoresistcomposition solvent. This reduction can result in a diminished oreliminated effectiveness on pattern collapse margin.

It would be desirable to have new polymers and underlayer coatingcompositions containing such polymers useful in forming a photoresistunderlayer.

SUMMARY

Provided is a polymer including a first repeating unit including anamino group protected by an alkoxycarbonyl group; a second repeatingunit including a nucleophilic group; and a third repeating unitincluding a crosslinkable group, wherein the first repeating unit, thesecond repeating unit, and the third repeating unit are different fromeach other.

Also provided is an underlayer coating composition including thepolymer, an acid catalyst, and a solvent.

Another aspect provides a coated substrate including a layer of theunderlayer coating composition disposed on a substrate; and aphotoresist layer disposed on the layer of the underlayer coatingcomposition.

Still another aspect provides a patterning method including applying alayer of the underlayer coating composition on a substrate; baking theunderlayer coating composition to form an underlayer film; applying alayer of a photoresist composition on the underlayer film to form aphotoresist layer; pattern-wise exposing the photoresist layer toactivating radiation; and developing the exposed photoresist layer toprovide a resist relief image.

DETAILED DESCRIPTION

Reference will now be made in detail to exemplary aspects, examples ofwhich are illustrated in the present description. In this regard, thepresent exemplary aspects may have different forms and should not beconstrued as being limited to the descriptions set forth herein.Accordingly, the exemplary aspects are merely described below to explainaspects of the present description. The terminology used herein is forthe purpose of describing particular aspects only and is not intended tobe limiting.

As used herein, the terms “a,” “an,” and “the” do not denote alimitation of quantity and are to be construed to cover both thesingular and the plural, unless otherwise indicated herein or clearlycontradicted by context. “Or” means “and/or” unless clearly indicatedotherwise. All ranges disclosed herein are inclusive of the endpoints,and the endpoints are independently combinable with each other. Thesuffix “(s)” is intended to include both the singular and the plural ofthe term that it modifies, thereby including at least one of that term.“Optional” or “optionally” means that the subsequently described eventor circumstance can or cannot occur, and that the description includesinstances where the event occurs and instances where it does not. Theterms “first,” “second,” and the like, herein do not denote an order,quantity, or importance, but rather are used to distinguish one elementfrom another. When an element is referred to as being “on” anotherelement, it may be directly in contact with the other element orintervening elements may be present therebetween. In contrast, when anelement is referred to as being “directly on” another element, there areno intervening elements present. It is to be understood that thedescribed components, elements, limitations, and/or features of aspectsmay be combined in any suitable manner in the various aspects.

As used herein, the term “hydrocarbon group” refers to an organiccompound having at least one carbon atom and at least one hydrogen atom,optionally substituted with one or more substituents where indicated;“alkyl group” refers to a straight or branched chain saturatedhydrocarbon having the specified number of carbon atoms and having avalence of one; “alkylene group” refers to an alkyl group having avalence of two; “hydroxyalkyl group” refers to an alkyl groupsubstituted with at least one hydroxyl group (—OH); “alkoxy group”refers to “alkyl-O—”; “carboxylic acid group” refers to a group havingthe formula “—C(═O)—OH”; “cycloalkyl group” refers to a monovalent grouphaving one or more saturated rings in which all ring members are carbon;“cycloalkylene group” refers to a cycloalkyl group having a valence oftwo; “alkenyl group” refers to a straight or branched chain, monovalenthydrocarbon group having at least one carbon-carbon double bond;“alkenoxy group” refers to “alkenyl-O—”; “alkenylene group” refers to analkenyl group having a valence of two; “cycloalkenyl group” refers to anon-aromatic cyclic divalent hydrocarbon group having at least threecarbon atoms, with at least one carbon-carbon double bond; “alkynylgroup” refers to a monovalent hydrocarbon group having at least onecarbon-carbon triple bond; “aryl group” refers to a monovalent aromaticmonocyclic or polycyclic ring system, and may include a group with anaromatic ring fused to at least one cycloalkyl or heterocycloalkyl ring;“arylene group” refers to an aryl group having a valence of two;“alkylaryl group” refers to an aryl group that has been substituted withan alkyl group; “arylalkyl group” refers to an alkyl group that has beensubstituted with an aryl group; “heterocycloalkyl group” refers to acycloalkyl group having 1-3 heteroatoms as ring members instead ofcarbon; “heterocycloalkylene group” refers to a heterocycloalkyl grouphaving a valence of two; “heteroaryl group” refers to an aromatic grouphaving 1-4 heteroatoms as ring members instead of carbon; “aryloxygroup” refers to “aryl-O—”; and “arylthio group” refers to “aryl-S—”.The prefix “hetero” means that the compound or group includes at leastone member that is a heteroatom (e.g., 1, 2, or 3 heteroatom(s)) insteadof a carbon atom, wherein the heteroatom(s) is each independently N, O,S, Si, or P. The prefix “halo” means a group including one more of afluoro, chloro, bromo, or iodo substituent instead of a hydrogen atom. Acombination of halo groups (e.g., bromo and fluoro), or only fluorogroups may be present. The term “(meth)acrylate” is inclusive of bothmethacrylate and acrylate, the term “(meth)allyl” is inclusive of bothmethallyl and allyl, and the term “(meth)acrylamide” is inclusive ofboth methacrylamide and acrylamide.

“Substituted” means that at least one hydrogen atom on the group isreplaced with another group, provided that the designated atom's normalvalence is not exceeded. When the substituent is oxo (i.e., ═O), thentwo hydrogens on the carbon atom are replaced. Combinations ofsubstituents or variables are permissible. Exemplary groups that may bepresent on a “substituted” position include, but are not limited to,nitro (—NO₂), cyano (—CN), hydroxyl (—OH), oxo (═O), amino (—NH₂), mono-or di-(C₁₋₆)alkylamino, alkanoyl (such as a C₂₋₆ alkanoyl group such asacyl), formyl (—C(═O)H), carboxylic acid or an alkali metal or ammoniumsalt thereof, C₂₋₆ alkyl ester (—C(═O)O-alkyl or —OC(═O)-alkyl), C₇₋₁₃aryl ester (—C(═O)O-aryl or —OC(═O)-aryl), amido (—C(═O)NR₂ wherein R ishydrogen or C₁₋₆ alkyl), carboxamido (—CH₂C(═O)NR₂ wherein R is hydrogenor C₁₋₆ alkyl), halogen (e.g., fluorine, chlorine, bromine), thiol(—SH), C₁₋₆ alkylthio (—S-alkyl), thiocyano (—SCN), C₁₋₆ alkyl, C₂₋₆alkenyl, C₂₋₆ alkynyl, C₁₋₆ haloalkyl, C₁₋₉ alkoxy, C₁₋₆ haloalkoxy,C₃₋₁₂ cycloalkyl, C₅₋₁₈ cycloalkenyl, C₆₋₁₂ aryl having at least onearomatic ring (e.g., phenyl, biphenyl, naphthyl, or the like, each ringeither substituted or unsubstituted aromatic), C₇₋₁₉ arylalkyl having 1to 3 separate or fused rings and from 6 to 18 ring carbon atoms,arylalkoxy having 1 to 3 separate or fused rings and from 6 to 18 ringcarbon atoms, C₇₋₁₂ alkylaryl, C₄₋₁₂ heterocycloalkyl, C₃₋₁₂ heteroaryl,C₁₋₆ alkyl sulfonyl (—S(═O)₂-alkyl), C₆₋₁₂ arylsulfonyl (—S(═O)₂-aryl),or tosyl (CH₃C₆H₄SO₂—). When a group is substituted, the indicatednumber of carbon atoms is the total number of carbon atoms in the group,excluding those of any substituents. For example, the group —CH₂CH₂CN isa C₂ alkyl group substituted with a cyano group.

Provided is a polymer including a first repeating unit including anamino group protected by an alkoxycarbonyl group; a second repeatingunit including a nucleophilic group; and a third repeating unitincluding a crosslinkable group, wherein the first repeating unit, thesecond repeating unit, and the third repeating unit are different fromeach other. The first repeating unit provides a high pKa amine group asa basic cleavage product via thermal deprotection, for example by curingof the polymer. Preferably, the deprotected amine group has a pKa thatis greater than 6. The disclosed polymer can improve pattern collapsemargins of BARC and EUV underlayers by changing the basicity upondeprotection. In addition, the polymer is self-crosslinkable through thenucleophilic group of the second repeating unit and the crosslinkablegroup of the third repeating unit. The self-crosslinking can decreasethe solubility of the crosslinked polymer so as to avoid dissolutionfrom the underlayer during processing. The use of at least threedifferent and particular types of repeating units in the polymer canprovide significantly improved performance over traditional methods ofcontrolling basicity with photobase generator additives orphoto-destroyable quencher additives.

As used herein, the term “copolymer” refers to polymers containing twoor more distinct repeating units. Thus, the disclosed polymericcompounds of the invention can be referred to herein as a “polymer” or a“copolymer.”

In an embodiment, the first repeating unit may be derived from a monomerof formula (1):

In formula (1), R^(a) is hydrogen, fluorine, a substituted orunsubstituted C₁₋₅ alkyl, or a substituted or unsubstituted C₁₋₅fluoroalkyl. Preferably, R^(a) is hydrogen or methyl.

In formula (1), each R^(k) is independently a halogen, a hydroxy, acarboxylic acid or ester, a thiol, a straight chain or branched C₁₋₂₀alkyl, a monocyclic or polycyclic C₃₋₂₀ cycloalkyl, a monocyclic orpolycyclic C₃₋₂₀ fluorocycloalkenyl, a monocyclic or polycyclic C₃₋₂₀heterocycloalkyl, a monocyclic or polycyclic C₆₋₂₀ aryl, or a monocyclicor polycyclic C₄₋₂₀ heteroaryl, each of which is substituted orunsubstituted; and n is an integer of 0 to 11. Preferably, R^(k) is astraight chain or branched C₁₋₂₀ alkyl and n is 1.

In formula (1), A is a single bond or a C₁₋₂ alkylene. Preferably, A isa single bond or a Cl alkylene to provide a 5- or 6-memberedheterocyclic ring.

In formula (1), R¹, R², and R³ are each independently a straight chainor branched C₁₋₂₀ alkyl, a monocyclic or polycyclic C₃₋₂₀ cycloalkyl, amonocyclic or polycyclic C₃₋₂₀ heterocycloalkyl, a straight chain orbranched C₂₋₂₀ alkenyl, a monocyclic or polycyclic C₃₋₂₀ cycloalkenyl, amonocyclic or polycyclic C₃₋₂₀ heterocycloalkenyl, a monocyclic orpolycyclic C₆₋₂₀ aryl, or a monocyclic or polycyclic C₄₋₂₀ heteroaryl,each of which is substituted or unsubstituted. In an embodiment, any twoof R¹, R², and R³ together optionally may form a ring. In a furtherembodiment, a polycyclic structure can be formed by R¹, R², and R³.

Exemplary first repeating units derived from a monomer of formula (1)include, but are not limited to, the following:

wherein R^(a) is as defined in formula (1).

In another embodiment, the first repeating unit may be derived from amonomer of formula (2):

In formula (2), R^(b) is hydrogen, fluorine, a substituted orunsubstituted C₁₋₅ alkyl, or a substituted or unsubstituted C₁₋₅fluoroalkyl. Preferably, R^(b) is hydrogen or methyl.

In formula (2), L¹ is a linking group. The linking group may includecarbon and may optionally include one or more heteroatoms. In anexample, L¹ may be a straight chain or branched C₁₋₂₀ alkylene, amonocyclic or polycyclic C₃₋₂₀ cycloalkylene, a monocyclic or polycyclicC₃₋₂₀ heterocycloalkylene, a monocyclic or polycyclic C₆₋₂₀ arylene, ora monocyclic or polycyclic C₄₋₂₀ heteroarylene, each of which issubstituted or unsubstituted. Preferably, L¹ is a C₁₋₅ alkylene or aC₃₋₁₂ cycloalkylene.

In formula (2), R⁴, R⁵, and R⁶ are each independently a straight chainor branched C₁₋₂₀ alkyl, a monocyclic or polycyclic C₃₋₂₀ cycloalkyl, amonocyclic or polycyclic C₃₋₂₀ heterocycloalkyl, a straight chain orbranched C₂₋₂₀ alkenyl, a monocyclic or polycyclic C₃₋₂₀ cycloalkenyl, amonocyclic or polycyclic C₃₋₂₀ heterocycloalkenyl, a monocyclic orpolycyclic C₆₋₂₀ aryl, or a monocyclic or polycyclic C₄₋₂₀ heteroaryl,each of which is substituted or unsubstituted. In an embodiment, any twoof R⁴, R⁵, and R⁶ together optionally may form a ring. In a furtherembodiment, a polycyclic structure can be formed by R⁴, R⁵, and R⁶.

Exemplary first repeating units derived from a monomer of formula (2)include, but are not limited to, the following:

wherein R^(b) is as defined in formula (2).

In an embodiment, the second repeating unit may be derived from amonomer of formula (3):

In formula (3), R^(c) is hydrogen, fluorine, a substituted orunsubstituted C₁₋₅ alkyl, or a substituted or unsubstituted C₁₋₅fluoroalkyl. Preferably, R^(c) is hydrogen or methyl.

In formula (3), L² is a substituted or unsubstituted C₁₋₃₀ alkylene, asubstituted or unsubstituted C₃₋₃₀ cycloalkylene, a substituted orunsubstituted C₃₋₃₀ heterocycloalkylene, a substituted or unsubstitutedC₆₋₃₀ arylene, a substituted or unsubstituted divalent C₇₋₃₀ arylalkyl,a substituted or unsubstituted C₃₋₃₀ heteroarylene, or a substituted orunsubstituted divalent C₄₋₃₀ heteroarylalkyl. Preferably, L² is asubstituted or unsubstituted C₁₋₁₀ alkylene.

In formula (3), Z¹ is a nucleophilic group that includes oxygen,nitrogen, or sulfur such as hydroxyl (—OH), carboxyl (—COOH), amine(—NH₂), thiol (—SH), or amido (—C(═O)NH₂) moiety. In an embodiment, Z¹is hydroxyl, carboxyl, thiol, amino, or amido. Preferably, Z¹ ishydroxyl.

In an embodiment, the third repeating unit may be derived from a monomerof formula (4):

In formula (4), R^(d) is hydrogen, fluorine, a substituted orunsubstituted C₁₋₅ alkyl, or a substituted or unsubstituted C₁₋₅fluoroalkyl. Preferably, R^(d) is hydrogen or methyl.

In formula (4), L³ is a single bond, a substituted or unsubstitutedC₁₋₃₀ alkylene, a substituted or unsubstituted C₃₋₃₀ cycloalkylene, asubstituted or unsubstituted C₃₋₃₀ heterocycloalkylene, a substituted orunsubstituted C₆₋₃₀ arylene, a substituted or unsubstituted divalentC₇₋₃₀ arylalkyl, a substituted or unsubstituted C₃₋₃₀ heteroarylene, ora substituted or unsubstituted divalent C₄₋₃₀ heteroarylalkyl.Preferably, L³ is a substituted or unsubstituted C₁₋₁₀ alkylene.

In formula (4), Z² is epoxy or lactone. For example, Z² may be epoxy,β-propiolactone, γ-butyrolactone, or δ-valerolactone, each of which canbe substituted or unsubstituted. Preferably, Z² is epoxy.

In an embodiment, the polymer includes 5 to 60 mole percent (mol %),preferably 5 to 30 mol % of the first repeating unit; 20 to 65 mol %,preferably 30 to 65 mol % of the second repeating unit; and 20 to 65 mol%, preferably 30 to 65 mol % of the third repeating unit, each based on100 mol % of total repeating units in the polymer. For example, thepolymer includes 5 to 60 mol % of the first repeating unit derived froma monomer of formula (1) or formula (2); 20 to 65 mol % of the secondrepeating unit derived from a monomer of formula (3); and 20 to 65 mol %of the third repeating unit derived from a monomer of formula (4), eachbased on 100 mol % of total repeating units in the polymer.

The polymer may have a weight average molecular weight (M_(w)) from2,000 grams per mole (g/mol) to 100,000 g/mol, for example, preferablyfrom 10,000 to 50,000 g/mol, more preferably from 12,000 to 30,000g/mol, with a polydispersity index (PDI) of 1.3 to 3, preferably 1.3 to2, more preferably 1.4 to 2. Molecular weight is determined by gelpermeation chromatography (GPC) using polystyrene standards.

Suitable polymers of the present invention can be readily prepared basedon and by analogy with the procedures described in the examples of thepresent application, which are readily understood by those of ordinaryskill in the art. For example, one or more monomers corresponding to therepeating units described herein may be combined, or fed separately,using suitable solvent(s) and initiator, and polymerized in a reactor.The monomer composition may further include additives, such as asolvent, a polymerization initiator, a curing catalyst (i.e., the acidcatalyst), and the like. For example, the polymer may be obtained bypolymerization of the respective monomers under any suitable conditions,such as by heating at an effective temperature, irradiation withactivating radiation at an effective wavelength, or a combinationthereof.

Also provided is an underlayer coating composition including the polymerdescribed herein, an acid catalyst, and a solvent. Typically, thepolymer is present in the underlayer coating composition in an amount offrom 70 to 99 wt %, more preferably 75 to 95 wt % of the solids contentof the underlayer coating composition.

The underlayer coating composition may further include one or morepolymers (“additional polymers”) in addition to the inventive polymerdescribed above. For example, the underlayer coating composition mayfurther include an additional polymer as described above but differentin composition, or a polymer that is similar to those described abovebut does not include each of the three different requisite monomertypes. Additionally or alternatively, the one or more additionalpolymers can include those well known in the art, for example,polyacrylates, polyvinylethers, polyesters, polynorbornenes,polyacetals, polyethylene glycols, polyamides, polyacrylamides,polyphenols, novolacs, styrenic polymers, and polyvinyl alcohols.

The acid catalyst may include a free acid and/or an acid generator thatcan function to promote hardening or crosslinking of compositioncomponents. Thermal-induced crosslinking of the underlayer coatingcomposition by activation of an acid generator is generally preferred.Examples of free acids include, but are not limited to, sulfonic acidssuch as methane sulfonic acid, ethane sulfonic acid, propyl sulfonicacid, phenyl sulfonic acid, toluene sulfonic acid, dodecylbenzenesulfonic acid, and trifluoromethyl sulfonic acid.

Typically, one or more free acids may be present in the underlayercoating composition in a concentration from 0.1 to 15 wt %, morepreferably 0.5 to 10 wt % of the solids content of the underlayercoating composition.

Suitable thermal acid generators (TAGs) include nonionic or ioniccompounds. Suitable nonionic thermal acid generators include, forexample, cyclohexyl trifluoromethyl sulfonate, methyl trifluoromethylsulfonate, cyclohexyl p-toluenesulfonate, methyl p-toluenesulfonate,cyclohexyl 2,4,6-triisopropylbenzene sulfonate, nitrobenzyl esters,benzoin tosylate, 2-nitrobenzyl tosylate,tris(2,3-dibromopropyl)-1,3,5-triazine-2,4,6-trione, alkyl esters oforganic sulfonic acids, p-toluenesulfonic acid, dodecylbenzenesulfonicacid, oxalic acid, phthalic acid, phosphoric acid, camphorsulfonic acid,2,4,6-trimethylbenzene sulfonic acid, triisopropylnaphthalene sulfonicacid, 5-nitro-o-toluene sulfonic acid, 5-sulfosalicylic acid,2,5-dimethylbenzene sulfonic acid, 2-nitrobenzene sulfonic acid,3-chlorobenzene sulfonic acid, 3-bromobenzene sulfonic acid,2-fluorocaprylnaphthalene sulfonic acid, dodecylbenzene sulfonic acid,1-naphthol-5-sulfonic acid, 2-methoxy-4-hydroxy-5-benzoyl-benzenesulfonic acid, and their salts, and combinations thereof. Suitable ionicthermal acid generators include, for example, dodecylbenzenesulfonicacid triethylamine salts, dodecylbenzenedisulfonic acid triethylaminesalts, p-toluene sulfonic acid-ammonium salts, sulfonate salts, such ascarbocyclic aryl and heteroaryl sulfonate salts, aliphatic sulfonatesalts, benzenesulfonate salts and ammonium triflate salts includingbenzylpyridium and benzylanilinium salts of triflic acid. Compounds thatgenerate a sulfonic acid or a triflic acid upon activation are generallysuitable. Preferred thermal acid generators include p-toluenesulfonicacid ammonium salts, ammonium triflate salts, and heteroaryl sulfonatesalts. In an embodiment, the acid catalyst is pyridiniump-toluenesulfonate.

Typically, one or more thermal acid generators may be present in theunderlayer coating composition in a concentration from 0.1 to 15 wt %,more preferably 0.5 to 10 wt % of the solids content of the underlayercoating composition.

The solvent component of the underlayer coating composition may be asingle solvent or may include a mixture of two or more distinctsolvents. Suitably, each of the multiple solvents may be miscible witheach other. Suitable solvents include, for example, one or moreoxyisobutyric acid esters, particularly methyl-2-hydroxyisobutyrate,2-hydroxyisobutyric acid, ethyl lactate or one or more of the glycolethers such as 2-methoxyethyl ether (diglyme), ethylene glycolmonomethyl ether, and propylene glycol monomethyl ether; solvents thathave both ether and hydroxy moieties such as methoxy butanol, ethoxybutanol, methoxy propanol, and ethoxy propanol; methyl2-hydroxyisobutyrate; esters such as methyl cellosolve acetate, ethylcellosolve acetate, propylene glycol monomethyl ether acetate,dipropylene glycol monomethyl ether acetate and other solvents such asdibasic esters, propylene carbonate and gamma-butyro lactone.

The underlayer coating composition may include one or more optionaladditives including, for example, surfactants and antioxidants. Suchoptional additives if used are each typically present in the underlayercoating composition in minor amounts such as from 0.01 to 10 wt % basedon solids content of the underlayer coating composition.

Typical surfactants include those which exhibit an amphiphilic nature,meaning that they may be both hydrophilic and hydrophobic at the sametime. Amphiphilic surfactants possess a hydrophilic head group orgroups, which have a strong affinity for water and a long hydrophobictail, which is organophilic and repels water. Suitable surfactants maybe ionic (i.e., anionic, cationic) or nonionic. Further examples ofsurfactants include silicone surfactants, poly(alkylene oxide)surfactants, and fluorochemical surfactants. Suitable non-ionicsurfactants include, but are not limited to, octyl and nonyl phenolethoxylates such as TRITON X-114, X-100, X-45, X-15 and branchedsecondary alcohol ethoxylates such as TERGITOL TMN-6 (The Dow ChemicalCompany, Midland, Mich. USA). Still further exemplary surfactantsinclude alcohol (primary and secondary) ethoxylates, amine ethoxylates,glucosides, glucamine, polyethylene glycols, poly(ethyleneglycol-co-propylene glycol), or other surfactants disclosed inMcCutcheon's Emulsifiers and Detergents, North American Edition for theYear 2000 published by Manufacturers Confectioners Publishing Co. ofGlen Rock, N.J. Nonionic surfactants that are acetylenic diolderivatives also may be suitable. Such surfactants are commerciallyavailable from Air Products and Chemicals, Inc. of Allentown, Pa. andsold under the trade names of SURFYNOL™ and DYNOL™. Additional suitablesurfactants include other polymeric compounds such as the tri-blockEO-PO-EO co-polymers PLURONIC™ 25R2, L121, L123, L31, L81, L101 and P123(BASF, Inc.).

An antioxidant can be added to prevent or minimize oxidation of organicmaterials in the underlayer coating composition. Suitable antioxidantsinclude, for example, phenol-based antioxidants, antioxidants composedof an organic acid derivative, sulfur-containing antioxidants,phosphorus-based antioxidants, amine-based antioxidants, antioxidantcomposed of an amine-aldehyde condensate and antioxidants composed of anamine-ketone condensate. Examples of the phenol-based antioxidantinclude substituted phenols such as 1-oxy-3-methyl-4-isopropylbenzene,2,6-di-tert-butylphenol, 2,6-di-tert-butyl-4-ethylphenol,2,6-di-tert-butyl-4-methylphenol,4-hydroxymethyl-2,6-di-tert-butylphenol, butyl.hydroxyanisole,2-(1-methylcyclohexyl)-4,6-dimethylphenol,2,4-dimethyl-6-tert-butylphenol, 2-methyl-4,6-dinonylphenol,2,6-di-tert-butyl-α-dimethylamino-p-cresol,6-(4-hydroxy-3,5-di-tert-butyl.anilino)2,4-bis.octyl-thio-1,3,5-triazine,n-octadecyl-3-(4′-hydroxy-3′,5′-di-tert-butyl.phenyl)propionate,octylated phenol, aralkyl-substituted phenols, alkylated p-cresol andhindered phenol; bis-, tris- and poly-phenols such as4,4′-dihydroxy.diphenyl, methylene.bis(dimethyl-4,6-phenol),2,2′-methylene-bis-(4-methyl-6-tert-butylphenol),2,2′-methylene-bis-(4-methyl-6-cyclohexyl.phenol),2,2′-methylene-bis-(4-ethyl-6-tert-butylphenol),4,4′-methylene-bis-(2,6-di-tert-butylphenol),2,2′-methylene-bis-(6-α-methyl-benzyl-p-cresol), methylene-crosslinkedpolyvalent alkylphenol,4,4′-butylidenebis-(3-methyl-6-tert-butylphenol),1,1-bis-(4-hydroxyphenyl)-cyclohexane,2,2′-dihydroxy-3,3′-di-(α-methylcyclohexyl)-5,5′-dimethyl.diphenylmethane,alkylated bisphenol, hindered bisphenol,1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene,tris-(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, andtetrakis-[methylene-3-(3′,5′-di-tert-butyl-4′-hydroxyphenyl)propionate]methane.Suitable antioxidants are commercially available, for example, Irganox™antioxidants (Ciba Specialty Chemicals Corp.).

The desired total solids content of the compositions will depend onfactors such as the desired final layer thickness. Typically, the solidscontent of the underlayer coating composition may be from 0.1 to 20 wt%, for example, from 0.1 to 10 wt %, more typically, from 0.11 to 5 wt%, based on the total weight of the underlayer coating composition. Asused herein, the “solids content” of an underlayer coating compositionrefers to all materials of the underlayer coating composition except thesolvent carrier.

The underlayer coating compositions may be prepared following knownprocedures. For example, the underlayer coating compositions may beprepared by combining the polymer, the acid catalyst, the solvent, andany optional components, in any order. The underlayer coatingcompositions may be used as is, or may be subjected to purificationprior to being coated on the substrate. Purification may involve, forexample, one or more of centrifugation, filtration, distillation,decantation, evaporation, treatment with ion exchange beads, and thelike.

The patterning methods of the present invention comprise applying alayer of the underlayer coating composition on a substrate; baking theunderlayer coating composition to form an underlayer film; applying alayer of a photoresist composition on the underlayer film to form aphotoresist layer; pattern-wise exposing the photoresist layer toactivating radiation; and developing the exposed photoresist layer toprovide a resist relief image.

A wide variety of substrates may be used in the patterning methods, withelectronic device substrates being typical. Suitable substrates include,for example, packaging substrates such as multichip modules; flat paneldisplay substrates; integrated circuit substrates; substrates for lightemitting diodes (LEDs) including organic light emitting diodes (OLEDs);semiconductor wafers; polycrystalline silicon substrates; and the like.Suitable substrates may be in the form of wafers such as those used inthe manufacture of integrated circuits, optical sensors, flat paneldisplays, integrated optical circuits, and LEDs. As used herein, theterm “semiconductor wafer” is intended to encompass “an electronicdevice substrate,” “a semiconductor substrate,” “a semiconductordevice,” and various packages for various levels of interconnection,including a single-chip wafer, multiple-chip wafer, packages for variouslevels, or other assemblies requiring solder connections. Suchsubstrates may be any suitable size. Typical wafer substrate diametersare 200 mm to 300 mm, although wafers having smaller and largerdiameters may be suitably employed according to the present invention.As used herein, the term “semiconductor substrate” includes anysubstrate having one or more semiconductor layers or structures whichmay optionally include active or operable portions of semiconductordevices. A semiconductor device refers to a semiconductor substrate uponwhich at least one microelectronic device has been or is being batchfabricated.

The substrates are typically composed of one or more of silicon,polysilicon, silicon oxide, silicon nitride, silicon oxynitride, silicongermanium, gallium arsenide, aluminum, sapphire, tungsten, titanium,titanium-tungsten, nickel, copper, and gold. The substrate may includeone or more layers and patterned features. The layers may include, forexample, one or more conductive layers such as layers of aluminum,copper, molybdenum, tantalum, titanium, tungsten, alloys, nitrides orsilicides of such metals, doped amorphous silicon or doped polysilicon,one or more dielectric layers such as layers of silicon oxide, siliconnitride, silicon oxynitride, or metal oxides, semiconductor layers, suchas single-crystal silicon, and combinations thereof. The layers can beformed by various techniques, for example, chemical vapor deposition(CVD) such as plasma-enhanced CVD (PECVD), low-pressure CVD (LPCVD) orepitaxial growth, physical vapor deposition (PVD) such as sputtering orevaporation, or electroplating.

It may be desired in certain patterning methods of the invention toprovide one or more lithographic layers such as a hardmask layer, forexample, a spin-on-carbon (SOC), amorphous carbon, or metal hardmasklayer, a CVD layer such as a silicon nitride (SiN) layer, silicon oxide(SiO) layer, or silicon oxynitride (SiON) layer, an organic or inorganicBARC layer, or a combination thereof, on an upper surface of thesubstrate prior to forming the photoresist underlayer of the invention.Such layers, together with an overcoated underlayer of the invention andphotoresist layer, form a lithographic material stack. Typicallithographic stacks which may be used in the patterning methods of theinvention include, for example, the following: SOClayer/underlayer/photoresist layer; SOC layer/SiONlayer/underlayer/photoresist layer; SOC layer/SiARClayer/underlayer/photoresist layer; SOC layer/metal hardmasklayer/underlayer/photoresist layer; amorphous carbonlayer/underlayer/photoresist layer; and amorphous carbon layer/SiONlayer/underlayer/photoresist layer.

The underlayer coating composition may be coated on the substrate by anysuitable means, such as spin-coating, slot-die coating, doctor blading,curtain-coating, roller-coating, spray-coating, dip-coating, and thelike. In the case of a semiconductor wafer, spin-coating is preferred.In a typical spin-coating method, the present compositions are appliedto a substrate which is spinning at a rate of 500 to 4000 rpm for aperiod of 15 to 90 seconds to obtain a desired layer of the condensedpolymer on the substrate. It will be appreciated by those skilled in theart that the thickness of the coated layer may be adjusted by changingthe spin speed, as well as the solids content of the composition. Anunderlayer formed from the underlayer coating composition typically hasa dried layer thickness of from 1 to 50 nm, more typically from 1 to 10nm.

The coated underlayer composition is optionally softbaked at arelatively low temperature to remove any solvent and other relativelyvolatile components from the underlayer composition. Typically, thesubstrate is baked at a temperature of less than or equal to 150° C.,preferably from 60 to 125° C., and more preferably from 90 to 115° C.The baking time is typically from 10 seconds to 10 minutes, preferablyfrom 30 seconds to 5 minutes, and more preferably from 6 to 90 seconds.When the substrate is a wafer, such baking step may be performed byheating the wafer on a hot plate. Such soft-baking step may be performedas part of the curing of the coating layer, or may be omittedaltogether.

The coated underlayer composition is then cured to form an underlayer.The composition should be sufficiently cured such that the underlayerdoes not intermix, or minimally intermixes, with a photoresist layer tobe formed on the underlayer. The coated underlayer composition may becured in an oxygen-containing atmosphere, such as air, or in an inertatmosphere, such as nitrogen and under conditions, such as heating,sufficient to provide a cured coating layer. This curing step ispreferably conducted on a hot plate-style apparatus, although ovencuring may be used to obtain equivalent results. The curing temperatureshould be sufficient for the acid catalyst to effect curing throughoutthe layer, for example, sufficient to allow a free acid to effectcrosslinking, or to allow a thermal acid generator to liberate acid andthe liberated acid to effect crosslinking where the acid catalyst is aTAG. Typically, the curing is conducted at a temperature of 150° C. orgreater, and preferably 150 to 450° C. It is more preferred that thecuring temperature is 180° C. or greater, still more preferably 200° C.or greater, and even more preferably from 200 to 400° C. The curing timeis typically from 10 seconds to 10 minutes, preferably from 30 secondsto 5 minutes, more preferably from 45 seconds to 2 minutes, and stillmore preferably from 45 to 90 seconds. Optionally, a ramped or amulti-stage curing process may be used. A ramped bake typically beginsat a relatively low (e.g., ambient) temperature that is increased at aconstant or varied ramp rate to a higher target temperature. Amulti-stage curing process involves curing at two or more temperatureplateaus, typically a first stage at a lower bake temperature and one ormore additional stages at a higher temperature. Conditions for suchramped or multi-stage curing processes are known to those skilled in theart, and may allow for omission of a preceding softbake process.

After curing of the underlayer composition, a photoresist layer isformed on the underlayer.

A wide variety of photoresists may be suitably used in the methods ofthe invention and are typically positive-tone materials. The particularphotoresists to be used will depend on the exposure wavelength used andgenerally comprise an acid-sensitive matrix polymer, a photoactivecomponent such as a photoacid generator, a solvent and optionaladditional components. Suitable photoresists are known to those skilledin the art and are commercially available, for example, variousphotoresist materials in the UV™ and EPIC™ product families from DuPontElectronics & Imaging. The photoresist can be applied to the substrateby known coating techniques such as described above with reference tothe underlayer composition, with spin-coating being typical. A typicalthickness for the photoresist layer is from 10 to 300 nm. Thephotoresist layer is typically next softbaked to minimize the solventcontent in the layer, thereby forming a tack-free coating and improvingadhesion of the layer to the substrate. The softbake can be conducted ona hotplate or in an oven, with a hotplate being typical. Typicalsoftbakes are conducted at a temperature of from 70 to 150° C., and atime of from 30 to 90 seconds.

The photoresist layer is next exposed to activating radiation through aphotomask to create a difference in solubility between exposed andunexposed regions. References herein to exposing a photoresistcomposition to radiation that is activating for the compositionindicates that the radiation is capable of forming a latent image in thephotoresist composition. The photomask has optically transparent andoptically opaque regions corresponding to regions of the resist layer tobe exposed and unexposed, respectively, by the activating radiation. Theexposure wavelength is typically sub-400 nm, and more typically, sub-300nm, such as 248 nm (KrF), 193 nm (ArF) or an EUV wavelength (e.g., 13.5nm). In a preferred aspect, the exposure wavelength is 193 nm or an EUVwavelength. The exposure energy is typically from 10 to 100 mJ/cm²,depending, for example, on the exposure tool and the components of thephotosensitive composition.

Following exposure of the photoresist layer, a post-exposure bake (PEB)is typically performed. The PEB can be conducted, for example, on ahotplate or in an oven. The PEB is typically conducted at a temperatureof from 70 to 150° C., and a time of from 30 to 90 seconds. A latentimage defined by the boundary between polarity-switched and unswitchedregions (corresponding to exposed and unexposed regions, respectively)is thereby formed. The photoresist layer is next developed to remove theexposed regions of the layer, leaving the unexposed regions forming apatterned photoresist layer. The developer is typically an aqueousalkaline developer, for example, a tetra-alkyl ammonium hydroxidesolution such as a tetramethylammonium hydroxide (TMAH) solution,typically 0.26 Normality (N) (2.38 wt %) TMAH. The developer may beapplied to the substrate by known techniques, for example, spin-coatingor puddle coating.

The pattern of the photoresist layer can then be transferred to one ormore underlying layers including the underlayer and to the substrate byappropriate etching techniques, such as by plasma etching usingappropriate gas species for each layer being etched. Depending on thenumber of layers and materials involved, pattern transfer may involvemultiple etching steps using different etching gases. The patternedphotoresist layer, underlayer, and other optional layers in thelithographic stack may be removed following pattern transfer of thesubstrate using conventional techniques. Optionally, one or more of thelayers of the stack may be removed following, or consumed during,pattern transfer to an underlying layer and prior to pattern transfer tothe substrate. The substrate is then further processed according toknown processes to form an electronic device.

Hereinafter, the present disclosure is illustrated in more detail withreference to examples. However, these examples are exemplary, and thepresent invention is not limited thereto.

EXAMPLES

Polymer Synthesis

Example 1

4-Hydroxyphenyl methacrylate (HQMA) (18.2 grams (g)), glycidylmethacrylate (GMA) (7.3 g), tert-butyl 4-(methacryloyloxy)piperidinemethacrylate (TBPMA) (4.6 g), and dimethyl2,2′-azobis(2-methylpropionate) (V601) (3.5 g) were dissolved in 32.5 gof ethyl lactate (EL)/gamma-butyrolactone (GBL) (EL:GBL=70:30 wt %ratio) in a first round-bottom flask (RBF) at room temperature withstirring. Separately, EL/GBL (37.5 g) was charged into a second RBFequipped with a condenser and a magnetic stirrer. The second flask washeated at 90° C. with stirring and the contents of the first RBF wereadded thereto dropwise over 3 hours. After monomer feeding wascompleted, the reaction mixture was stirred for an additional hour at90° C. The reaction mixture was cooled to room temperature andprecipitated to methyl tert-butyl ether (MTBE, 1000 g). The solids wereisolated and dried under vacuum at 40° C. for 16 hrs. The copolymerincludes the repeating units HQMA:GMA:TBPMA in a ratio of 60.6:30.4:9.0and has a M_(w) of 9.2 kg/mol as determined by GPC).

Example 2

HQMA (15.1 g), GMA (5.9 g), TBPMA (9.0 g), and V601 (2.6 g) weredissolved in 32.5 g of EL/GBL (70:30 wt/w ratio) in a first RBF at roomtemperature with stirring. Separately, EL/GBL (37.5 g) was charged intoa second RBF equipped with a condenser and a magnetic stirrer. Thesecond flask was heated at 90° C. with stirring and the contents of thefirst RBF were added thereto dropwise over 3 hours. After monomerfeeding was completed, the reaction mixture was stirred for anadditional hour at 90° C. The reaction mixture was cooled to roomtemperature and precipitated with MTBE (1000 g). The solids wereisolated and dried under vacuum at 40° C. for 16 hrs. The copolymerincludes the repeating units HQMA:GMA:TBPMA in a ratio of 56.5:27.0:16.5and has a M_(w) of 11.8 kg/mol as determined by GPC).

Example 3

2-Hydroxyethyl methacrylate (HEMA) (15.9 g), GMA (5.5 g), TBPMA (5.5 g),and V601 (5.6 g) were dissolved in 32.5 g of EL/GBL (70:30 wt/w ratio)in a first RBF at room temperature with stirring. Separately, EL/GBL(37.5 g) was charged into a second RBF equipped with a condenser and amagnetic stirrer. The second flask was heated at 80° C. with stirringand the contents of the first RBF were added thereto dropwise over 2hours. After monomer feeding was completed, the reaction mixture wasstirred for an additional hour at 80° C. The reaction mixture was cooledto room temperature and precipitated with MTBE (1000 g). The resultingproduct was re-dissolved in THF (120 g) and precipitated with MTBE (1500g). The solids were isolated and dried under vacuum at 40° C. for 16hrs. The copolymer includes the repeating units HEMA:GMA:TBPMA in aratio of 63.4:26.6:10.0 and has a M_(w) of 7.7 kg/mol as determined byGPC).

Example 4

HQMA (19.8 g), GMA (7.9 g), tert-butyl4-(methacryloyloxy)-4-methylpiperidine-1-carboxylate (TBMPMA) (5.3 g),and V601 (3.5 g) were dissolved in 32.5 g of EL/GBL (70:30 wt/w ratio)in a first RBF at room temperature with stirring. Separately, EL/GBL(37.5 g) was charged into a second RBF equipped with a condenser and amagnetic stirrer. The second flask was heated at 90° C. with stirringand the contents of the first RBF were added thereto dropwise over 3hours. After monomer feeding was completed, the reaction mixture wasstirred for an additional hour at 90° C. The reaction mixture was cooledto room temperature and precipitated with MTBE (1000 g). The solids wereisolated and dried under vacuum at 40° C. for 16 hrs. The copolymerincludes the repeating units HQMA:GMA:TBMPMA in a ratio of58.9:30.9:10.2 and has a M_(w) of 9.0 kg/mol as determined by GPC).

Example 5

HQMA (19.6 g), GMA (7.8 g), tert-butyl4-ethyl-4-(methacryloyloxy)piperidine-1-carboxylate (TBEPMA) (5.5 g),and V601 (3.5 g) were dissolved in 32.5 g of EL/GBL (70:30 wt/w ratio)in a first RBF at room temperature with stirring. Separately, EL/GBL(37.5 g) was charged into a second RBF equipped with a condenser and amagnetic stirrer. The second flask was heated at 90° C. with stirringand the contents of the first RBF were added thereto dropwise over 3hours. After monomer feeding was completed, the reaction mixture wasstirred for an additional hour at 90° C. The reaction mixture was cooledto room temperature and precipitated with MTBE (1000 g). The solids wereisolated and dried under vacuum at 40° C. for 16 hrs. The copolymerincludes the repeating units HQMA:GMA:TBEPMA in a ratio of 59.3:31.0:9.7and has a M_(w) of 10.5 kg/mol as determined by GPC).

Example 6

HQMA (20.5 g), GMA (7.8 g), 2-((tert-butoxycarbonyl)amino)ethylmethacrylate (TBAEMA) (4.4 g), and V601 (3.5 g) were dissolved in 32.5 gof EL/GBL (70:30 wt/w ratio) in a first RBF at room temperature withstirring. Separately, EL/GBL (37.5 g) was charged into a second RBFequipped with a condenser and a magnetic stirrer. The second flask washeated at 90° C. with stirring and the contents of the first RBF wereadded thereto dropwise over 3 hours. After monomer feeding wascompleted, the reaction mixture was stirred for an additional hour at90° C. The reaction mixture was cooled to room temperature andprecipitated with MTBE (1000 g). The solids were isolated and driedunder vacuum at 40° C. for 16 hrs. The copolymer includes the repeatingunits HQMA:GMA:TBAEMA in a ratio of 60.1:29.5:10.4 and has a M_(w) of11.3 kg/mol as determined by GPC).

Example 7

GMA (21.8 g) and HQMA (18.2 g) were dissolved in 40 g of EL in a firstRBF at room temperature with stirring. Separately, EL (80 g) was chargedinto a second RBF equipped with a condenser and a magnetic stirrer. Thesecond flask was heated at 90° C. with stirring and the contents of thefirst RBF were added thereto dropwise over 3 hours. After monomerfeeding was completed, the reaction mixture was stirred for anadditional hour at 90° C. The reaction mixture was cooled to roomtemperature and precipitated with MTBE (1000 g). The solids wereisolated and dried under vacuum at 40° C. for 16 hrs. The copolymerincludes the repeating units GMA:HQMA in a ratio of 60.3:39.7 and has aM_(w) of 4.7 kg/mol as determined by GPC).

Preparation of Anti-Reflective Compositions

Compositions were prepared by combining one of the copolymers of Example1 to 7, 2,4,6-trimethylpyridinium p-toluenesulfonate, methyl2-hydroxyisobutyrate (8.308 g), 1-methoxy-2-propyl acetate (20.769 g),and methyl-2-pyrrolidone (0.593 g). Table 1 lists the compositions.

TABLE 1 Copolymer 2,4,6-trimethylpyridinium Example Copolymer amount (g)p-toluenesulfonate (g)  8 Example 1 0.326 0.004  9 Example 2 0.326 0.00410 Example 1 0.314 0.016 11 Example 2 0.314 0.016 12 Example 1 0.2870.033 13 Example 2 0.287 0.033 14 Example 3 0.287 0.033 15 Example 40.287 0.033 16 Example 5 0.287 0.033 17 Example 6 0.287 0.033 18*Example 7 0.326 0.004 *denotes a comparative example

Example 19: Film Strip Testing

The compositions were spin-coated onto 200 mm silicon wafers and bakedat 205° C. for 60 seconds by MARK track (Step 1). The coated wafer wasexposed to 30 mL of PGMEA:PGME (30:70 wt % ratio) for 90 seconds,spun-dry to form thin film, and cured at 110° C. for 60 seconds (Step2). The film thickness was measured at initial coated film (Step 1) andpost baked film (Step 2) by Opti-probe. The amount of stripping wasdetermined to be the difference between the Step 1 and Step 2thicknesses.

Example 20: Lithographic Testing

Silicon wafers were coated on a TEL Lithius 300 mm wafer track with AR™40 organic bottom anti-reflective coating and cured at 205° C. for 60seconds to form a 700 Å first BARC layer. The compositions of Examples 8to 18 were then coated over the first BARC layer and cured at 205° C.for 60 seconds to form a 390 Å second layer. EPIC™ IM7011(Meth)acrylate-based ArF Photoresist (DuPont Electronics & Imaging) wascoated over the second layer and soft-baked at 110° C. for 60 seconds toform a 900 Å thickness layer. The wafers were exposed on a NIKON 610CArF immersion scanner at 1.3 NA, 0.98/0.78 inner/outer sigma, dipoleillumination, through a photomask to form 40/80 nm line/space pattern.The wafers were post-exposure baked (PEB) at 95° C. for 60 seconds. Thewafers were developed with 0.26 N TMAH developer and spun-dry to formpositive tone patterns. The patterned wafers were inspected using aCD-SEM tool.

The results for Examples 19 and 20 are provided in Table 2.

TABLE 2 Film strip Pattern Collapse Sample loss (Å) EoP (mJ/cm²) CD (nm)Example 8 −1.2 36.4 39.0 Example 9 −0.8 35.6 40.2 Example 10 −1.1 36.739.3 Example 11 −1.0 35.7 39.2 Example 12 −1.2 36.0 40.4 Example 13 −0.736.2 39.3 Example 14 −0.8 38.0 42.2 Example 15 −1.0 36.0 41.0 Example 16−0.9 37.8 42.0 Example 17 −0.5 37.4 41.2 Example 18* −1.6 37.6 38.9*denotes comparative example

As shown in Table 2, the underlayer coating compositions of Examples 8to 17 achieved a pattern collapse improvement with reduction of filmstrip loss relative to Example 18 (comparative).

While this disclosure has been described in connection with what ispresently considered to be practical exemplary aspects, it is to beunderstood that the invention is not limited to the disclosed aspects,but, on the contrary, is intended to cover various modifications andequivalent arrangements included within the spirit and scope of theappended claims.

What is claimed is:
 1. A coated substrate, comprising: a layer of anunderlayer coating composition disposed on a substrate; and aphotoresist layer disposed on the layer of the underlayer coatingcomposition, wherein the underlayer coating composition comprises apolymer comprising: a first repeating unit comprising an amino groupprotected by an alkoxycarbonyl group; a second repeating unit comprisinga nucleophilic group; and a third repeating unit comprising acrosslinkable group, wherein the first repeating unit, the secondrepeating unit, and the third repeating unit are different from eachother.
 2. The coated substrate of claim 1, wherein the first repeatingunit is derived from a monomer of formula (1):

wherein, R^(a) is hydrogen, fluorine, a substituted or unsubstitutedC₁₋₅ alkyl, or a substituted or unsubstituted C₁₋₅ fluoroalkyl; eachR^(k) is independently a halogen, a hydroxy, a carboxylic acid or ester,a thiol, a straight chain or branched C₁₋₂₀ alkyl, a monocyclic orpolycyclic C₃₋₂₀ cycloalkyl, a monocyclic or polycyclic C₃₋₂₀fluorocycloalkenyl, a monocyclic or polycyclic C₃₋₂₀ heterocycloalkyl, amonocyclic or polycyclic C₆₋₂₀ aryl, or a monocyclic or polycyclic C₄₋₂₀heteroaryl, each of which is substituted or unsubstituted; A is a singlebond or a C₁₋₂ alkylene; R¹, R², and R³ are each independently astraight chain or branched C₁₋₂₀ alkyl, a monocyclic or polycyclic C₃₋₂₀cycloalkyl, a monocyclic or polycyclic C₃₋₂₀ heterocycloalkyl, astraight chain or branched C₂₋₂₀ alkenyl, a monocyclic or polycyclicC₃₋₂₀ cycloalkenyl, a monocyclic or polycyclic C₃₋₂₀ heterocycloalkenyl,a monocyclic or polycyclic C₆₋₂₀ aryl, or a monocyclic or polycyclicC₄₋₂₀ heteroaryl, each of which is substituted or unsubstituted, and anytwo of R¹, R², and R³ together optionally form a ring; and n is aninteger of 0 to
 11. 3. The coated substrate of claim 1, wherein thefirst repeating unit is derived from a monomer of formula (2):

wherein, R^(b) is hydrogen, fluorine, a substituted or unsubstitutedC₁₋₅ alkyl, or a substituted or unsubstituted C₁₋₅ fluoroalkyl; L¹ is alinking group; and R⁴, R⁵, and R⁶ are each independently a straightchain or branched C₁₋₂₀ alkyl, a monocyclic or polycyclic C₃₋₂₀cycloalkyl, a monocyclic or polycyclic C₃₋₂₀ heterocycloalkyl, astraight chain or branched C₂₋₂₀ alkenyl, a monocyclic or polycyclicC₃₋₂₀ cycloalkenyl, a monocyclic or polycyclic C₃₋₂₀ heterocycloalkenyl,a monocyclic or polycyclic C₆₋₂₀ aryl, or a monocyclic or polycyclicC₄₋₂₀ heteroaryl, each of which is substituted or unsubstituted, and anytwo of R⁴, R⁵, and R⁶ together optionally form a ring.
 4. The coatedsubstrate of claim 1, wherein the second repeating unit is derived froma monomer of formula (3):

wherein R^(c) is hydrogen, fluorine, a substituted or unsubstituted C₁₋₅alkyl, or a substituted or unsubstituted C₁₋₅ fluoroalkyl; L² is asubstituted or unsubstituted C₁₋₃₀ alkylene, a substituted orunsubstituted C₃₋₃₀ cycloalkylene, a substituted or unsubstituted C₃₋₃₀heterocycloalkylene, a substituted or unsubstituted C₆₋₃₀ arylene, asubstituted or unsubstituted divalent C₇₋₃₀ arylalkyl, a substituted orunsubstituted C₃₋₃₀ heteroarylene, or a substituted or unsubstituteddivalent C₄₋₃₀ heteroarylalkyl; and Z¹ is hydroxyl, carboxyl, thiol,amino, or amido.
 5. The coated substrate of claim 1, wherein the thirdrepeating unit is derived from a monomer of formula (4):

wherein, R^(d) is hydrogen, fluorine, a substituted or unsubstitutedC₁₋₅ alkyl, or a substituted or unsubstituted C₁₋₅ fluoroalkyl; L³ is asingle bond, a substituted or unsubstituted C₁₋₃₀ alkylene, asubstituted or unsubstituted C₃₋₃₀ cycloalkylene, a substituted orunsubstituted C₃₋₃₀ heterocycloalkylene, a substituted or unsubstitutedC₆₋₃₀ arylene, a substituted or unsubstituted divalent C₇₋₃₀ arylalkyl,a substituted or unsubstituted C₃₋₃₀ heteroarylene, or a substituted orunsubstituted divalent C₄₋₃₀ heteroarylalkyl; and Z² is epoxy orlactone.
 6. The coated substrate of claim 1, wherein the polymercomprises: 5 to 60 mole percent of the first repeating unit; 20 to 65mole percent of the second repeating unit; and 20 to 65 mole percent ofthe third repeating unit, each based on 100 mole percent of totalrepeating units in the polymer.
 7. The coated substrate of claim 1,wherein the underlayer coating composition further comprises: an acidcatalyst; and a solvent.
 8. The coated substrate of claim 1, wherein theunderlayer coating composition further comprises an additional polymerthat is different from the polymer.
 9. A patterning method, comprising:applying a layer of an underlayer coating composition on a substrate;baking the underlayer coating composition to form an underlayer film;applying a layer of a photoresist composition on the underlayer film toform a photoresist layer; pattern-wise exposing the photoresist layer toactivating radiation; and developing the exposed photoresist layer toprovide a resist relief image, wherein the underlayer coatingcomposition comprises a polymer comprising: a first repeating unitcomprising an amino group protected by an alkoxycarbonyl group; a secondrepeating unit comprising a nucleophilic group; and a third repeatingunit comprising a crosslinkable group, wherein the first repeating unit,the second repeating unit, and the third repeating unit are differentfrom each other.
 10. The method of claim 9, wherein the first repeatingunit is derived from a monomer of formula (1):

wherein, R^(a) is hydrogen, fluorine, a substituted or unsubstitutedC₁₋₅ alkyl, or a substituted or unsubstituted C₁₋₅ fluoroalkyl; eachR^(k) is independently a halogen, a hydroxy, a carboxylic acid or ester,a thiol, a straight chain or branched C₁₋₂₀ alkyl, a monocyclic orpolycyclic C₃₋₂₀ cycloalkyl, a monocyclic or polycyclic C₃₋₂₀fluorocycloalkenyl, a monocyclic or polycyclic C₃₋₂₀ heterocycloalkyl, amonocyclic or polycyclic C₆₋₂₀ aryl, or a monocyclic or polycyclic C₄₋₂₀heteroaryl, each of which is substituted or unsubstituted; A is a singlebond or a C₁₋₂ alkylene; R¹, R², and R³ are each independently astraight chain or branched C₁₋₂₀ alkyl, a monocyclic or polycyclic C₃₋₂₀cycloalkyl, a monocyclic or polycyclic C₃₋₂₀ heterocycloalkyl, astraight chain or branched C₂₋₂₀ alkenyl, a monocyclic or polycyclicC₃₋₂₀ cycloalkenyl, a monocyclic or polycyclic C₃₋₂₀ heterocycloalkenyl,a monocyclic or polycyclic C₆₋₂₀ aryl, or a monocyclic or polycyclicC₄₋₂₀ heteroaryl, each of which is substituted or unsubstituted, and anytwo of R¹, R², and R³ together optionally form a ring; and n is aninteger of 0 to
 11. 11. The method of claim 9, wherein the firstrepeating unit is derived from a monomer of formula (2):

wherein, R^(b) is hydrogen, fluorine, a substituted or unsubstitutedC¹⁻⁵ alkyl, or a substituted or unsubstituted C₁₋₅ fluoroalkyl; L¹ is alinking group; and R⁴, R⁵, and R⁶ are each independently a straightchain or branched C₁₋₂₀ alkyl, a monocyclic or polycyclic C₃₋₂₀cycloalkyl, a monocyclic or polycyclic C₃₋₂₀ heterocycloalkyl, astraight chain or branched C2-20 alkenyl, a monocyclic or polycyclicC₃₋₂₀ cycloalkenyl, a monocyclic or polycyclic C₃₋₂₀ heterocycloalkenyl,a monocyclic or polycyclic C₆₋₂₀ aryl, or a monocyclic or polycyclicC₄₋₂₀ heteroaryl, each of which is substituted or unsubstituted, and anytwo of R⁴, R⁵, and R⁶ together optionally form a ring.
 12. The method ofclaim 9, wherein the second repeating unit is derived from a monomer offormula (3):

wherein R^(c) is hydrogen, fluorine, a substituted or unsubstituted C₁₋₅alkyl, or a substituted or unsubstituted C₁₋₅ fluoroalkyl; L² is asubstituted or unsubstituted C₁₋₃₀ alkylene, a substituted orunsubstituted C₃₋₃₀ cycloalkylene, a substituted or unsubstituted C₃₋₃₀heterocycloalkylene, a substituted or unsubstituted C₆₋₃₀ arylene, asubstituted or unsubstituted divalent C₇₋₃₀ arylalkyl, a substituted orunsubstituted C₃₋₃₀ heteroarylene, or a substituted or unsubstituteddivalent C₄₋₃₀ heteroarylalkyl; and Z¹ is hydroxyl, carboxyl, thiol,amino, or amido.
 13. The method of claim 9, wherein the third repeatingunit is derived from a monomer of formula (4):

wherein, R^(d) is hydrogen, fluorine, a substituted or unsubstitutedC₁₋₅ alkyl, or a substituted or unsubstituted C₁₋₅ fluoroalkyl; L³ is asingle bond, a substituted or unsubstituted C₆₋₃₀ alkylene, asubstituted or unsubstituted C₃₋₃₀ cycloalkylene, a substituted orunsubstituted C₃₋₃₀ heterocycloalkylene, a substituted or unsubstitutedC₆₋₃₀ arylene, a substituted or unsubstituted divalent C₇₋₃₀ arylalkyl,a substituted or unsubstituted C₃₋₃₀ heteroarylene, or a substituted orunsubstituted divalent C₄₋₃₀ heteroarylalkyl; and Z² is epoxy orlactone.
 14. The method of claim 9, wherein the polymer comprises: 5 to60 mole percent of the first repeating unit; 20 to 65 mole percent ofthe second repeating unit; and 20 to 65 mole percent of the thirdrepeating unit, each based on 100 mole percent of total repeating unitsin the polymer.
 15. The method of claim 9, wherein the underlayercoating composition further comprises: an acid catalyst; and a solvent.16. The method of claim 9, wherein the underlayer coating compositionfurther comprises an additional polymer that is different from thepolymer.
 17. The method of claim 9, wherein the activating radiationcomprises a wavelength of 193 nanometers.
 18. The method of claim 9,wherein the activating radiation comprises an EUV wavelength.